Enzymatic analysis of eucalyptus harvest residue decomposition by lentinula edodes for enhanced crop management and...

Eucalypt wastes (EW), comprising bark, leaf and branches, when retained and distributed on-site are a valuable source of nutrients for soil and microbial biomass. This study investigates the acceleration of EW biodegradation through the introduction of the edible fungus Lentinula edodes in-vitro cultures. Production of enzymes, ergosterol and organic matter consumption (OMC) were assessed in the spent mushroom compost over 90-days incubation. Concurrently, the residual solid decreased to 71.9%, with 35% reduction in lignin and hemicellulose and 28.5% loss of cellulose. EW substrate was supplemented with rice bran (RB) and soybean bran (SB) in different ratios to explore L. edodes enzyme production during substrate decomposition. Composition of EW supplemented with cereal brans (CB) provided high production of endoglucanase (2,300 U / kg) within 45 days, β-glucosidase (375 U / kg) in 60 days. Productions of 80,000 U / kg of xylanase and 195 U / kg of β-xylosidase occurred in 45 days of cultivation. Laccase (3,750 U / kg) was determined in 60 days, along with manganese peroxidase (MnP) (6,000 U / kg) in 75 days in EW: SB (90:10). Ergosterol extraction (45 mg / kg) and L. edodes mycelial biomass (11 g / kg) was obtained in all combinations of EW and CB. The maximum biological efficiency (BE) of 67% was achieved in a single cycle with EW: RB 90:10. Overall, L. edodes emerges as a promising resource for EW biodegradation, and this work sheds light on applications for fungus-based degradation in forest eucalypt plantations. For fungus-based degradation in forest eucalyptus plantations. Parte superior do formulário.